import dateUtil from '../../../common/utils/date';

const newArray = function(start, end) {
	let result = [];
	for (let i = start; i <= end; i++) {
		result.push(i);
	}
	return result;
};

export const equalDate = function(dateA, dateB) {
	return dateA === dateB || new Date(dateA).getTime() === new Date(dateB).getTime();
};

export const toDate = function(date) {
	return isDate(date) ? new Date(date) : null;
};

export const isDate = function(date) {
	if (date === null || date === undefined) return false;
	if (isNaN(new Date(date).getTime())) return false;
	return true;
};

export const formatDate = function(date, format) {
	date = toDate(date);
	if (!date) return '';
	return dateUtil.format(date, format || 'yyyy-MM-dd');
};

export const parseDate = function(string, format) {
	return dateUtil.parse(string, format || 'yyyy-MM-dd');
};

export const getDayCountOfMonth = function(year, month) {
	if (month === 3 || month === 5 || month === 8 || month === 10) {
		return 30;
	}

	if (month === 1) {
		if (year % 4 === 0 && year % 100 !== 0 || year % 400 === 0) {
			return 29;
		} else {
			return 28;
		}
	}

	return 31;
};

export const getFirstDayOfMonth = function(date) {
	const temp = new Date(date.getTime());
	temp.setDate(1);
	return temp.getDay();
};

export const DAY_DURATION = 86400000;

export const getStartDateOfMonth = function(year, month) {
	const result = new Date(year, month, 1);
	const day = result.getDay();

	if (day === 0) {
		result.setTime(result.getTime() - DAY_DURATION * 7);
	} else {
		result.setTime(result.getTime() - DAY_DURATION * day);
	}

	return result;
};

export const getWeekNumber = function(src) {
	const date = new Date(src.getTime());
	date.setHours(0, 0, 0, 0);
	// Thursday in current week decides the year.
	date.setDate(date.getDate() + 3 - (date.getDay() + 6) % 7);
	// January 4 is always in week 1.
	const week1 = new Date(date.getFullYear(), 0, 4);
	// Adjust to Thursday in week 1 and count number of weeks from date to week 1.
	return 1 + Math.round(((date.getTime() - week1.getTime()) / 86400000 - 3 + (week1.getDay() + 6) % 7) / 7);
};

export const prevMonth = function(src) {
	const year = src.getFullYear();
	const month = src.getMonth();
	const date = src.getDate();

	const newYear = month === 0 ? year - 1 : year;
	const newMonth = month === 0 ? 11 : month - 1;

	const newMonthDayCount = getDayCountOfMonth(newYear, newMonth);
	if (newMonthDayCount < date) {
		src.setDate(newMonthDayCount);
	}

	src.setMonth(newMonth);
	src.setFullYear(newYear);

	return new Date(src.getTime());
};

export const nextMonth = function(src) {
	const year = src.getFullYear();
	const month = src.getMonth();
	const date = src.getDate();

	const newYear = month === 11 ? year + 1 : year;
	const newMonth = month === 11 ? 0 : month + 1;

	const newMonthDayCount = getDayCountOfMonth(newYear, newMonth);
	if (newMonthDayCount < date) {
		src.setDate(newMonthDayCount);
	}

	src.setMonth(newMonth);
	src.setFullYear(newYear);

	return new Date(src.getTime());
};

export const getRangeHours = function(ranges) {
	const hours = [];
	let disabledHours = [];

	(ranges || []).forEach(range => {
		const value = range.map(date => date.getHours());

		disabledHours = disabledHours.concat(newArray(value[0], value[1]));
	});

	if (disabledHours.length) {
		for (let i = 0; i < 24; i++) {
			hours[i] = disabledHours.indexOf(i) === -1;
		}
	} else {
		for (let i = 0; i < 24; i++) {
			hours[i] = false;
		}
	}

	return hours;
};

export const limitRange = function(date, ranges, format = 'yyyy-MM-dd HH:mm:ss') {
	if (!ranges || !ranges.length) return date;

	const len = ranges.length;

	date = dateUtil.parse(dateUtil.format(date, format), format);
	for (let i = 0; i < len; i++) {
		const range = ranges[i];
		if (date >= range[0] && date <= range[1]) {
			return date;
		}
	}

	let maxDate = ranges[0][0];
	let minDate = ranges[0][0];

	ranges.forEach(range => {
		minDate = new Date(Math.min(range[0], minDate));
		maxDate = new Date(Math.max(range[1], maxDate));
	});

	return date < minDate ? minDate : maxDate;
};
